PIR LED Security Light Circuit Schematic Notes The PIR sensor requires an initial stabilization time of about 10 to 60 seconds in order to function properly. During this time, the sensor gets familiar ...

This circuit is from the GLOLAB web page. The document referenced here includes an excellent design as well as an excellent tutorial on PIR devices. You've probably seen these ...

Unlike infrared optical sensors that use an LED transmitter and IR receiver, the PIR emits nothing. As its “passive” name suggests, it responds only to infrared energy radiated by the object ...